#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
int main()
{
	int score, i = 0, sum = 0;
    loop:printf("Data:");
	     scanf("%d", &score);
	     if (score != -1)
	    {
		   sum = sum + score;
		   i++;
		   goto loop;
	     }
	if (i != 0)
		printf("ave:%d\n", sum / i);
	return 0;
}